The perpendicular distance, of the line x–12=y+2–1=z+32 from the point P(2, –10, 1) is: [2025]
(2)
x–12=y+2–1=z+32=λ (say)
Any point on the line is given by
M(x,y,z)≡(2λ+1,–λ–2,2λ–3)
Also, PM→=(2λ+1–2)i^+(–λ–2+10)j^+(2λ–3–1)k^
=(2λ–1)i^+(–λ+8)j^+(2λ–4)k^ ... (i)
∵ PM→·n→=0
⇒ (2λ–1)2+(–λ+8)(–1)+(2λ–4)2=0
⇒ 4λ–2+λ–8+4λ–8=0
⇒ 9λ–18=0 ⇒ λ=2
∴ |PM→|=32+62+02=45=35 [Using (i)]